WT1 gene is a zinc finger transcription factor isolated as a gene etiologically associated with Wilms' tumor and its gene product (WT1 protein) has a structure comprising a repression domain, an activation domain, and a zinc finger.
The inventors previously reported that the expression level of WT1 gene is high in acute leukemia, that this expression level is inversely correlated with the prognosis of the disease, and that the MRD (minimal residual disease) of acute leukemia can be detected by measuring said expression level [Blood, Vol. 84, No. 9, p 3071 (1994)]. Furthermore, the inventors found that by measuring the expression level of WT1 gene, various types of solid cancer and tissue atypia can be detected (WO97/39354).
Determination of said expression level of WT1 gene which comprises measuring the transcription or translation product of WT1 gene has a great clinical significance in a search for the presence of a WT1 related disease.